Schaum's outline of trigonometry - Moyer, Robert; Ayres, Frank 1901-1994 (New York McGraw-Hill Education, 2018)
Electronic reproduction.
Keywords: Trigonometry; Trigonometry -- Outlines, syllabi, etc; Angles (Geometry) -- Outlines, syllabi, etc; Trigonometrical functions -- Outlines, syllabi, etc; Functions -- Outlines, syllabi, etc; Triangle -- Outlines, syllabi, etc; Triangularization (Mathematics) -- Outlines, syllabi, etc; Inversions (Geometry) -- Outlines, syllabi, etc; Numbers, Complex -- Outlines, syllabi, etc; Electronic books